96 
BULLETIN OF THE BUREAU OF FISHERIES. 
UPPER PRIEST LAKE, IDAHO. 
Upper Priest Lake, a small body of water, lies 3 km. (1.8 miles) north of Priest 
Lake, connected with it by a winding thoroughfare passing through marshy land. 
We investigated only the lower part of this lake, which is quite marshy, and that 
during a rain. At the southern end the shores are steeper and more rocky than 
those of Priest Lake. 
The lake has a very irregular outline (fig. 17) and is surrounded on all sides 
by hills. The arms of the lake as they run into little valleys give all conditions 
of depth — very shallow places and, out in the more open parts, deep water. 
The water of the lake is clear; the disk was read at 9 m., and the surface water 
had a rather low temperature, 18.1° C. In July the thermocline was between 6 
and 15 m. The net plankton was most abundant in this region. 
UPPER TWIN LAKE, IDAHO. 
This is a very shallow lake, 5.5 m. (18 feet) deep, surrounded on three sides 
with marshy land. The water at this time of the year was greenish-brown, and 
the thermocline had entirely disappeared. The lake is slightly alkaline and shows 
enormous quantities of algae. A 1-meter haul was sufficient to clog the net. 
WILLIAMS LAKE, WASH. 
Williams Lake is small and shallow, the maximum depth being 15 m. (49.2 
feet). The water was fairly transparent, the disk not disappearing from view 
until a depth of 5 m. was reached. The net plankton was most abundant in the 
upper 2 m. 
This lake was reported to contain bass and perch in 1911. It has been stocked 
with silver trout, and in 1920 was reported as one of the best lakes for silver- trout 
fishing. 
WRIGHT LAKE, IDAHO. 
This lake (see also p. 85) has a maximum depth of only 7 m. (22.9 feet), and, as 
is usually the case in shallow lakes, it was well supplied with plankton, especially 
phytoplankton. The Crustacea consisted of Cyclops, Diaptomus leptopus, Daphnia 
hyalina, and Diaphanosoma leuchteribergianum. Daphnia hyalina composed about 
one-third of the total number of Crustacea. (See Table 12, p. 135.) About 17 per 
cent of the Crustacea consisted of nauplii. Notholca and Conochilus were the 
only rotifers found, and they numbered 2,200 individuals per cubic meter of water. 
The algse consisted chiefly of Anabsena and Gloeotrichia. The fish-food supply was 
unusually large, and the lake ought to yield a large number of fish. 
